IPv6 NTP multicast mode configuration example

As shown in Figure 41, Switch C functions as the NTP server for multiple devices on different network segments and synchronizes the time among multiple devices.

• Configure Switch C's local clock as a reference source, with stratum level 2.

• Configure Switch C to operate in IPv6 multicast server mode and send IPv6 multicast messages from VLAN-interface 2.

• Configure Switch A and Switch D to operate in IPv6 multicast client mode and receive IPv6 multicast messages through VLAN-interface 3 and VLAN-interface 2, respectively.

1. Assign an IP address to each interface, and make sure the switches can reach each other, as shown in Figure 41. (Details not shown.)

2. Configure Switch C:

   # Enable the NTP service.

   <SwitchC> system-view
   [SwitchC] ntp-service enable
   

   # Specify the local clock as the reference source, with stratum level 2.

   [SwitchC] ntp-service refclock-master 2
   

   # Configure Switch C to operate in IPv6 multicast server mode and send multicast messages through VLAN-interface 2.

   [SwitchC] interface vlan-interface 2
   [SwitchC-Vlan-interface2] ntp-service ipv6 multicast-server ff24::1
   

3. Configure Switch D:

   # Enable the NTP service.

   <SwitchD> system-view
   [SwitchD] ntp-service enable
   

   # Configure Switch D to operate in IPv6 multicast client mode and receive multicast messages on VLAN-interface 2.

   [SwitchD] interface vlan-interface 2
   [SwitchD-Vlan-interface2] ntp-service ipv6 multicast-client ff24::1
   

4. Verify the configuration:

   Switch D and Switch C are on the same subnet, so Switch D can do the following:

   • Receive the IPv6 multicast messages from Switch C without being enabled with the IPv6 multicast functions.

   • Synchronize to Switch C.

   # Verify that Switch D has synchronized to Switch C, and the clock stratum level is 3 on Switch D and 2 on Switch C.

   [SwitchD-Vlan-interface2] display ntp-service status
    Clock status: synchronized
    Clock stratum: 3
    System peer: 3000::2
    Local mode: bclient
    Reference clock ID: 165.84.121.65
    Leap indicator: 00
    Clock jitter: 0.000977 s
    Stability: 0.000 pps
    Clock precision: 2^-18
    Root delay: 0.00000 ms
    Root dispersion: 8.00578 ms
    Reference time: d0c60680.9754fb17  Wed, Dec 29 2010 19:12:00.591
   

   # Verify that an IPv6 NTP association has been established between Switch D and Switch C.

   [SwitchD-Vlan-interface2] display ntp-service ipv6 sessions
   Notes: 1 source(master), 2 source(peer), 3 selected, 4 candidate, 5 configured.
   
    Source:  [1234]3000::2
    Reference: 127.127.1.0           Clock stratum: 2
    Reachabilities: 111              Poll interval: 64
    Last receive time: 23            Offset: -0.0
    Roundtrip delay: 0.0             Dispersion: 0.0
   
    Total sessions: 1
   

5. Configure Switch B:

   Because Switch A and Switch C are on different subnets, you must enable the IPv6 multicast functions on Switch B before Switch A can receive IPv6 multicast messages from Switch C.

   # Enable IPv6 multicast functions.

   <SwitchB> system-view
   [SwitchB] ipv6 multicast routing
   [SwitchB-mrib6] quit
   [SwitchB] interface vlan-interface 2
   [SwitchB-Vlan-interface2] ipv6 pim dm
   [SwitchB-Vlan-interface2] quit
   [SwitchB] vlan 3
   [SwitchB-vlan3] port ten-gigabitethernet 1/0/1
   [SwitchB-vlan3] quit
   [SwitchB] interface vlan-interface 3
   [SwitchB-Vlan-interface3] mld enable
   [SwitchB-Vlan-interface3] mld static-group ff24::1
   [SwitchB-Vlan-interface3] quit
   [SwitchB] mld-snooping
   [SwitchB-mld-snooping] quit
   [SwitchB] interface ten-gigabitethernet 1/0/1
   [SwitchB-Ten-GigabitEthernet1/0/1] mld-snooping static-group ff24::1 vlan 3
   

6. Configure Switch A:

   # Enable the NTP service.

   <SwitchA> system-view
   [SwitchA] ntp-service enable
   

   # Configure Switch A to operate in IPv6 multicast client mode and receive IPv6 multicast messages on VLAN-interface 3.

   [SwitchA] interface vlan-interface 3
   [SwitchA-Vlan-interface3] ntp-service ipv6 multicast-client ff24::1
   

7. Verify the configuration:

   # Verify that Switch A has synchronized to Switch C, and the clock stratum level is 3 on Switch A and 2 on Switch C.

   [SwitchA-Vlan-interface3] display ntp-service status
    Clock status: synchronized
    Clock stratum: 3
    System peer: 3000::2
    Local mode: bclient
    Reference clock ID: 165.84.121.65
    Leap indicator: 00
    Clock jitter: 0.165741 s
    Stability: 0.000 pps
    Clock precision: 2^-18
    Root delay: 0.00534 ms
    Root dispersion: 4.51282 ms
    Reference time: d0c61289.10b1193f  Wed, Dec 29 2010 20:03:21.065
   

   # Verify that an IPv6 NTP association has been established between Switch A and Switch C.

   [SwitchA-Vlan-interface3] display ntp-service ipv6 sessions
   Notes: 1 source(master), 2 source(peer), 3 selected, 4 candidate, 5 configured.
   
    Source:   [124]3000::2
    Reference: 127.127.1.0           Clock stratum: 2
    Reachabilities: 2                Poll interval: 64
    Last receive time: 71            Offset: -0.0
    Roundtrip delay: 0.0             Dispersion: 0.0
   
    Total sessions: 1